Temporary vessel occlusion in spontaneously hypertensive and normotensive rats

1994 ◽  
Vol 80 (6) ◽  
pp. 1085-1090 ◽  
Author(s):  
Warren R. Selman ◽  
Sana U. Bhatti ◽  
C. Cory Rosenstein ◽  
W. David Lust ◽  
Robert A. Ratcheson
Keyword(s):  
Spontaneously Hypertensive Rats ◽  
Hypertensive Rats ◽  
Vessel Occlusion ◽  
Content Type ◽  
Spontaneously Hypertensive ◽  
Significant Difference ◽  
Clip Application ◽  
The Mean ◽  
Improved Design ◽  
Fine Print

✓ Temporary occlusion of an intracranial artery is frequently necessary in the surgical management of intracranial aneurysms, arteriovenous malformations, and tumors. While the risks of vessel damage associated with clip application have been lessened by improved design, the threat of ischemic damage remains. It is unclear whether multiple, brief periods of clip application are more or less safe than a single period of occlusion, and whether the underlying cerebrovascular status influences the outcome from either method. The effect of each of these paradigms (single: 1-hour occlusion; multiple: three 20-minute episodes separated by 10 minutes of reperfusion) on histopathological outcome was assessed in a middle cerebral artery (MCA) occlusion model using both normotensive and spontaneously hypertensive rats. The mean volume of infarction (± standard error of the mean) was not different between the single-ischemic (49.4 ± 17.3 cu mm) and the multiple-ischemic (42.9 ± 12.9 cu mm) episode groups of normotensive rats, whereas in the spontaneously hypertensive rats a significant difference existed between the volume of infarction for the single-occlusion group (126.7 ± 18.7 cu mm) and the multiple-occlusion group (162.4 ± 15.5 cu mm) (p < 0.05). The metabolic data obtained from spontaneously hypertensive animals did not provide an explanation for the larger infarction in that there were no significant differences between the single- and multiple-occlusion groups with respect to tissue glucose, adenosine triphosphate, or lactate levels. The results suggest that intermittent reperfusion may have different effects depending not only on the degree and duration of ischemia and reperfusion, but also on the underlying cerebrovascular status.

Neuroprotective effect of postischemic administration of progesterone in spontaneously hypertensive rats with focal cerebral ischemia

2000 ◽  
Vol 92 (5) ◽  
pp. 848-952 ◽  
Author(s):  
Yoshiaki Kumon ◽  
Soon C. Kim ◽  
Paul Tompkins ◽  
Alan Stevens ◽  
Saburo Sakaki ◽  
...  
Keyword(s):  
Body Weight ◽  
Cerebral Ischemia ◽  
Neurological Deficit ◽  
Spontaneously Hypertensive Rats ◽  
Focal Cerebral Ischemia ◽  
Hypertensive Rats ◽  
Content Type ◽  
Spontaneously Hypertensive ◽  
Mca Occlusion ◽  
Fine Print

Object. Exogenous progesterone has been shown to reduce brain edema and ischemia-induced cell damage and to improve physiological and neurological function during the early stage of focal cerebral ischemia. In the present study, the authors assessed the neuroprotective potential of progesterone during the late stage of ischemia in a transient middle cerebral artery (MCA) occlusion model in the rat.Methods. Forty-eight male spontaneously hypertensive rats were randomly assigned to six groups. Progesterone was dissolved in dimethyl sulfoxide (DMSO). In four groups of rats, the dissolved progesterone (4 mg/kg or 8 mg/kg) was administered for 2 or 7 days after ischemia. In two control groups DMSO was administered for 2 or 7 days after ischemia. Occlusion of the MCA was induced by insertion of an intraluminal suture, and reperfusion was accomplished by withdrawal of the suture. Treatment was initiated on reperfusion, which followed 2 hours of MCA occlusion, and continued once a day. Lesion volume, neurological deficit, and body weight loss were measured 2 or 7 days after ischemia, depending on the animal group.Treatment with a high dose of progesterone (8 mg/kg) resulted in reductions in lesion size, neurological deficits, and body weight, compared with control rats.Conclusions. Administration of progesterone to male rats 2 hours after MCA occlusion reduces ischemic brain damage and improves neurological deficit even 7 days after ischemia.

Gamma knife radiosurgery for intracranial metastatic melanoma: a 6-year experience

2002 ◽  
Vol 97 ◽  
pp. 494-498 ◽  
Author(s):  
Jorge Gonzalez-martinez ◽  
Laura Hernandez ◽  
Lucia Zamorano ◽  
Andrew Sloan ◽  
Kenneth Levin ◽  
...  
Keyword(s):  
Prognostic Factors ◽  
Brain Metastases ◽  
Metastatic Melanoma ◽  
Gamma Knife Radiosurgery ◽  
Tumor Control ◽  
Karnofsky Performance Scale ◽  
Content Type ◽  
Significant Difference ◽  
The Mean ◽  
Fine Print

Object. The purpose of this study was to evaluate retrospectively the effectiveness of stereotactic radiosurgery for intracranial metastatic melanoma and to identify prognostic factors related to tumor control and survival that might be helpful in determining appropriate therapy. Methods. Twenty-four patients with intracranial metastases (115 lesions) metastatic from melanoma underwent radiosurgery. In 14 patients (58.3%) whole-brain radiotherapy (WBRT) was performed, and in 12 (50%) chemotherapy was conducted before radiosurgery. The median tumor volume was 4 cm3 (range 1–15 cm3). The mean dose was 16.4 Gy (range 13–20 Gy) prescribed to the 50% isodose at the tumor margin. All cases were categorized according to the Recursive Partitioning Analysis classification for brain metastases. Univariate and multivariate analyses of survival were performed to determine significant prognostic factors affecting survival. The mean survival was 5.5 months after radiosurgery. The analyses revealed no difference in terms of survival between patients who underwent WBRT or chemotherapy and those who did not. A significant difference (p < 0.05) in mean survival was observed between patients receiving immunotherapy or those with a Karnofsky Performance Scale (KPS) score of greater than 90. Conclusions. The treatment with systemic immunotherapy and a KPS score greater than 90 were factors associated with a better prognosis. Radiosurgery for melanoma-related brain metastases appears to be an effective treatment associated with few complications.

Enalapril attenuates cardiorenal damage in nitric-oxide-deficient spontaneously hypertensive rats

2004 ◽  
Vol 106 (3) ◽  
pp. 337-343 ◽  
Author(s):  
Leila M. M. PEREIRA ◽  
Daniele G. BEZERRA ◽  
Denise L. MACHADO ◽  
Carlos A. MANDARIM-DE-LACERDA
Keyword(s):  
Nitric Oxide ◽  
Body Mass ◽  
Structural Damage ◽  
Spontaneously Hypertensive Rats ◽  
Left Ventricular ◽  
Hypertensive Rats ◽  
Spontaneously Hypertensive ◽  
Genetic Hypertension ◽  
Lv Mass ◽  
Significant Difference

Stereological structural alterations of the heart and kidney were studied in four groups (n=5) of spontaneously hypertensive rats (SHRs) treated for 30 days: (i) control, (ii) NG-nitro-L-arginine methyl ester [L-NAME; nitric oxide (NO) synthesis inhibitor] alone, (iii) enalapril alone and (iv) L-NAME plus enalapril. Blood pressure (BP) was elevated significantly in NO-deficient SHRs (rats receiving L-NAME) or significantly lower in enalapril-treated SHRs. Co-administration of L-NAME and enalapril caused a 20% decrease in BP compared with untreated SHRs. NO-deficient SHRs had a decrease in body mass, but this loss of body mass was prevented efficiently in the enalapril-treated group. Enalapril treatment decreased the left ventricular (LV) mass index in SHRs, even in animals with NO synthesis blocked. NO deficiency in SHRs caused a larger decrease in the number of LV cardiomyocyte nuclei, which had a negative correlation with both LV mass index and BP. The volume-weighted glomerular volume (VWGV) separated the SHRs into two groupings: (i) control and NO-deficient SHRs, and (ii) enalapril- and L-NAME plus enalapril-treated SHRs. There was a significant difference between these two groupings, with VWGV being more than 15% smaller in the latter compared with the former grouping. The present findings reinforce the evidence that enalapril efficiently treats genetic hypertension, and demonstrate that this effect is observed even when NO synthesis is inhibited. Enalapril administration also decreases cardiac and renal structural damage caused by genetic hypertension, as well as by the interaction between genetic hypertension and NO deficiency.

scholarly journals Sustained density of neuroendocrine cells with aging precedes development of prostatic hyperplasia in spontaneously hypertensive rats

BMC Urology ◽  
2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Yuki Kyoda ◽  
Koji Ichihara ◽  
Kohei Hashimoto ◽  
Ko Kobayashi ◽  
Fumimasa Fukuta ◽  
...  
Keyword(s):  
Spontaneously Hypertensive Rats ◽  
Prostatic Hyperplasia ◽  
Neuroendocrine Cells ◽  
Initial Growth ◽  
Hypertensive Rats ◽  
Initial Development ◽  
Spontaneously Hypertensive ◽  
Significant Difference ◽  
The Difference ◽  
Wistar Kyoto

Abstract Background Neuroendocrine (NE) cells may have an impact on the development and initial growth of benign prostatic hyperplasia (BPH) according to previous human studies. Methods To explore the relationship of NE cells and BPH development, we compared the density of NE cells and also prostatic weight in spontaneously hypertensive rats (SHR), which develop by aging, and Wistar-Kyoto rats (WKY) as control. The total weights of the epithelium and stroma in the ventral lobes of 8-, 12, 16-, 28- and 56-week-old SHR and WKY were calculated using Image J software. NE cells in the ventral prostatic ducts (VPd) were quantified using immunohistochemical staining for serotonin. Results Although there was no significant difference in the estimated total weight of the epithelium and stroma in the ventral lobes adjusted by body weight (ES weight) between the two groups at 8, 12 and 16 weeks of age, ES weight was significantly greater in the SHR group than in the WKT group at 28 and 56 weeks. The density of NE cells in the VPd decreased with aging in the WKY group, whereas it was sustained until 16 weeks and then decreased with aging in the SHR group. The difference in the density between the two groups was most marked at 16 weeks of age. Conclusion In the natural history of BPH, NE cells may play an important role in the initial development of BPH because sustained density of NE cells in the VPd precedes the development of prostatic hyperplasia.

Ventricular volume change in childhood

2002 ◽  
Vol 97 (3) ◽  
pp. 584-590 ◽  
Author(s):  
Chris Xenos ◽  
Spyros Sgouros ◽  
Kalyan Natarajan
Keyword(s):  
Statistical Difference ◽  
Linear Regression Analysis ◽  
Ventricular Volume ◽  
Intracranial Volume ◽  
Normal Children ◽  
Content Type ◽  
Ventricular Volumes ◽  
Significant Difference ◽  
The Mean ◽  
Fine Print

Object. The aim of this study was to construct a model of age-related changes in ventricular volume in a group of normal children ages 1 month to 15 years, which could be used for comparative studies of cerebrospinal fluid circulation disorders and cerebral atrophy developmental syndromes. Methods. A magnetic resonance imaging—based segmentation technique was used to measure ventricular volumes in normal children; each volume was then plotted against the child's age. In addition, intracranial volumes were measured and the ratio of ventricular to intracranial volume was calculated and plotted against age. The study group included 71 normal children, 39 boys and 32 girls, whose ages ranged from 1 month to 15.3 years (mean 84.9 months, median 79 months). The mean ventricular volume was 21.3 cm3 for the whole group, 22.7 cm3 in boys and 19.6 cm3 in girls (p = 0.062, according to t-tests). The mean ventricular volume at 12 months for the whole group was 17 cm3 (20 cm3 in boys and 15 cm3 in girls), representing 65% of the volume achieved by 15 years of age (87% in boys and 53% in girls). The volume increased by a factor of 1.53, to 26 cm3 (23 cm3 in males and 28 cm3 in females, increase factors of 1.15 and 1.86, respectively) at 15 years of age. The change in ventricular volume with age is not linear, but follows a segmental pattern. These age periods were defined as: 0 to 3, 4 to 6, 7 to 10, and 11 to 16 years. A statistical difference based on sex was only demonstrated in the first 6 years of life. The mean ventricular volume for the first 6-year period was 22.4 cm3 in boys and 15.7 cm3 in girls, and the difference was significant for the two sexes (linear regression analysis for age and sex, significant according to analysis of variance regression at 0.007, p = 0.108 for age, p = 0.012 for sex). Thereafter, there was no significant difference in ventricular volume between boys and girls with further growth. The ratio of ventricular volume to intracranial volume was 0.0175 for the whole group, 0.017 in boys and 0.018 in girls (p = 0.272, according to t-tests). At 12 months of age the ratio was 0.019; it stabilized to 0.015 at 8 years of age, and increased to 0.018 at 15 years of age. No statistical difference based on sex was demonstrated with growth. Conclusions. The ventricular volume in normal children increases with age by a factor of 1.5; the increase is in a nonlinear segmental pattern. Boys have significantly higher ventricular volumes only in the first 6 years of life. The ventricular/intracranial volume ratio remains stable throughout childhood.

scholarly journals Twelve-Week Protocatechuic Acid Administration Improves Insulin-Induced and Insulin-Like Growth Factor-1-Induced Vasorelaxation and Antioxidant Activities in Aging Spontaneously Hypertensive Rats

Nutrients ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 699 ◽  
Author(s):  
Kunanya Masodsai ◽  
Yi-Yuan Lin ◽  
Rungchai Chaunchaiyakul ◽  
Chia-Ting Su ◽  
Shin-Da Lee ◽  
...  
Keyword(s):  
Growth Factor ◽  
Spontaneously Hypertensive Rats ◽  
Protocatechuic Acid ◽  
Antioxidant Activities ◽  
Vehicle Control ◽  
Insulin Like Growth Factor ◽  
Hypertensive Rats ◽  
Spontaneously Hypertensive ◽  
Significant Difference ◽  
Nos Inhibitors

Protocatechuic acid (PCA), a strong antioxidant, has been reported for its cardiovascular-protective effects. This study aimed to investigate the effects of PCA administration on vascular endothelial function, mediated by insulin and insulin-like growth factor-1 (IGF-1), and antioxidant activities in aging hypertension. Thirty-six-week-old male aging spontaneously hypertensive rats were randomly divided into vehicle control (SHR) and PCA (SHR+PCA) groups, while age-matched Wistar–Kyoto rats (WKY) served as the normotensive vehicle control group. The oral PCA (200 mg/kg/day) was administered daily for a total of 12 weeks. When the rats reached the age of 48 weeks, the rat aortas were isolated for the evaluation of vascular reactivity and Western blotting. Also, nitric oxide (NO) production and antioxidant activities were examined among the three groups. The results showed that, when compared with the SHR group, the insulin-induced and IGF-1-induced vasorelaxation were significantly improved in the SHR+PCA group. There was no significant difference in the endothelium-denuded vessels among the three groups. After the pre-incubation of phosphatidylinositol 3-kinase (PI3K) or NO synthase (NOS) inhibitors, the vasorelaxation was abolished and comparable among the three groups. The protein levels of insulin receptors, IGF-1 receptors, phospho-protein kinase B (p-Akt)/Akt, and phospho-endothelial NOS (p-eNOS)/eNOS in aortic tissues were significantly enhanced in the SHR+PCA group when compared with the SHR group. Moreover, significant improvements of nitrate/nitrite concentration and antioxidant activities, including superoxide dismutase, catalase, and total antioxidants, were also found in the SHR+PCA group. In conclusion, the 12 weeks of PCA administration remarkably improved the endothelium-dependent vasorelaxation induced by insulin and IGF-1 in aging hypertension through enhancing the PI3K–NOS–NO pathway. Furthermore, the enhanced antioxidant activities partly contributed to the improved vasorelaxation.

Beneficial effect of simvastatin and pravastatin treatment on adverse cardiac remodelling and glomeruli loss in spontaneously hypertensive rats

2005 ◽  
Vol 108 (4) ◽  
pp. 349-355 ◽  
Author(s):  
Daniele G. BEZERRA ◽  
Carlos A. MANDARIM-de-LACERDA
Keyword(s):  
Left Ventricle ◽  
Spontaneously Hypertensive Rats ◽  
Renal Cortex ◽  
Interstitial Fibrosis ◽  
Treated Group ◽  
Left Ventricular ◽  
Control Group ◽  
Hypertensive Rats ◽  
Spontaneously Hypertensive ◽  
Significant Difference

The aim of the present study was to investigate the possibility of different effects of the hydrophobic statin simvastatin and the hydrophilic statin pravastatin on the remodelling process in the overloaded left ventricle and renal cortex of SHRs (spontaneously hypertensive rats). Fifteen SHRs were treated for 40 days with simvastatin, pravastatin or placebo (water) via orogastric administration. Left ventricle and renal cortex were examined by light microscopy and stereology. LV (left ventricular) cardiomyocyte nuclei (N[cmn]) and glomeruli (N[gl]) numbers were estimated by the dissector method. BP (blood pressure) and serum triacylglycerols (triglycerides) were lower in the statin-treated groups than in the untreated control group. The volume density of the interstitial connective tissue was smaller and length density of the intramyocardial arteries, as well as the arteries/cardiomyocyte ratio, was greater in the statin-treated groups than in the control group. No difference was observed between the two statin-treated groups. The cross-sectional cardiomyocyte area was significantly smaller in the simvastatin-treated group than in the control or pravastatin-treated groups, and it was smaller in the pravastatin-treated group than in the control group. N[cmn] and N[gl] were greater in the two statin-treated groups than in the control group, but no significant difference was observed between the two statin-treated groups. In conclusion, administration of the statins simvastatin and pravastatin to SHRs effectively prevented the elevation in BP and serum triaclyglycerols, and also attenuated adverse cardiac and kidney remodelling by preventing LV hypertrophy, enhancing myocardial vascularization with the decrease in interstitial fibrosis and attenuating cardiomyocyte and glomerular loss.

Results of degenerative spondylolisthesis treated with posterior decompression alone via a new surgical approach

2001 ◽  
Vol 95 (1) ◽  
pp. 11-16 ◽  
Author(s):  
Tomoaki Kinoshita ◽  
Isao Ohki ◽  
Kenneth R. Roth ◽  
Kageharu Amano ◽  
Hideshige Moriya
Keyword(s):  
Japanese Orthopaedic Association ◽  
Degenerative Spondylolisthesis ◽  
Spinal Instability ◽  
Content Type ◽  
Significant Difference ◽  
Potential Alternative ◽  
The Mean ◽  
New Surgical Technique ◽  
Fine Print

Object. The purpose of this study was to assess radiologically demonstrated results and clinical outcomes in patients with degenerative spondylolisthesis who underwent posterior decompressive surgery via a new (unilateral) approach. This approach allows surgeons to perform central and bilateral decompression while only stripping the muscles unilaterally, thus preserving the posterior osteoligamentous complexes. Methods. The authors evaluated 51 consecutive patients in whom surgery was performed between 1987 and 1996. The mean follow-up period was 4.7 years. There was no statistically significant difference between the pre- and postoperative measurements in percentage of vertebral slippage. Postoperative dynamic angulation statistically decreased compared with its preoperative value (p < 0.05). Improvement of an average of 67% was shown on the Japanese Orthopaedic Association scale, and in 78% of these patients, good to excellent results were demonstrated. Secondary fusion was required in only three patients (5.9%). Conclusions. This new surgical technique offers a potential alternative for the treatment of degenerative spondylolisthesis in a minimally invasive manner, avoiding the risk of causing or aggravating postoperative spinal instability.

Intra-Erythrocyte Sodium and (Na+,K+-Activated)-ATPase Concentration and Urinary Aldosterone Excretion in Spontaneously Hypertensive Rats

1981 ◽  
Vol 60 (2) ◽  
pp. 229-232 ◽  
Author(s):  
G. Berglund ◽  
L. Sigström ◽  
S. Lundin ◽  
B. E. Karlberg ◽  
H. Herlitz
Keyword(s):  
Spontaneously Hypertensive Rats ◽  
Sodium Concentration ◽  
Intracellular Sodium ◽  
Hypertensive Rats ◽  
Spontaneously Hypertensive ◽  
Wistar Kyoto Rats ◽  
Significant Difference ◽  
Intracellular Sodium Concentration ◽  
Erythrocyte Sodium ◽  
Wistar Kyoto

1. Intra-erythrocyte sodium, potassium, ATP and (Na+,K+-activated)-ATPase concentrations and urinary aldosterone excretion were compared in 3-month-old spontaneously hypertensive rats (n = 11) and normotensive Wistar-Kyoto control rats (n = 11). 2. Spontaneously hypertensive rats exhibited significantly higher intra-erythrocyte sodium concentration (5.5 ± 1.3 vs 4.0 ± 1.1 mmol/l of erythrocytes, P < 0.01). No significant difference was found in intra-erythrocyte potassium, ATP or (Na+,K+-activated)-ATPase concentration. 3. Mean urinary aldosterone excretion was significantly lower in spontaneously hypertensive rats (66.3 ± 6.5 pmol/24 h) than in Wistar-Kyoto rats (90.5 ± 10.6 pmol/24 h, P < 0.01). No significant relationship between urinary aldosterone and intra-erythrocyte sodium concentration was found in spontaneously hypertensive or Wistar-Kyoto rats or in the pooled group. 4. These results are thus consistent with previous findings of an increased intracellular sodium concentration in spontaneously hypertensive rats, but do not support the hypothesis that aldosterone is a dominant regulator of intracellular sodium concentration.

Concentration-Dependent Effects of Insulin on Ca2+ Influx in Vascular Smooth Muscle Cells of Normotensive and Spontaneously Hypertensive Rats

1993 ◽  
Vol 85 (4) ◽  
pp. 425-429 ◽  
Author(s):  
Zhiming Zhu ◽  
Martin Tepel ◽  
Marcus Neusser ◽  
Norbert Mehring ◽  
Walter Zidek
Keyword(s):  
Smooth Muscle ◽  
Vascular Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Vascular Smooth Muscle Cells ◽  
Spontaneously Hypertensive Rats ◽  
Muscle Cells ◽  
Hypertensive Rats ◽  
Maximum Increase ◽  
Spontaneously Hypertensive ◽  
Significant Difference

1. The effect of insulin on cytosolic free Ca2+ concentration was measured using fura-2 in vascular smooth muscle cells of normotensive and spontaneously hypertensive rats. 2. In both strains, insulin increased cytosolic free Ca2+ concentration in a concentration range between 10−6 and 10−3 units/ml. The maximum increase in cytosolic free Ca2+ concentration was observed with 10−5 units/ml insulin (107 +25 and 82+27 nmol/l in spontaneously hypertensive rats and normotensive rats, respectively). 3. The effect of insulin was dependent on extracellular Ca2+ and was enhanced by stimulation of protein kinase C. 4. Thus insulin appears to induce a Ca2+ influx in vascular smooth muscle cells only over a certain range of concentrations. No significant difference in the response to insulin of cells from normotensive and hypertensive rats was observed.

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